Process for manufacturing lubricants



Passed July as, was

UNITED STATES PATENT OFFICE i PROCESS FOR MANUFACTURING LUBRICANTS Fran:Rudolf Moser, Amsterdam, Netherlands, assignor to Shell Development.Company, San 'FranciscmCaliL, a'corporation of Delaware No Drawmg.

cation March 21,1935, Se-

Anv rial No. 12,247. In the Netherlands March 26,

1934 8 Claims.

The invention relates to a process for manufacturing lubricants, such asmineral lubricating carboxylic acids are much more suitable for theobject in view and moreover frequently have still other properties whichare of importance in ap- 18 plying the lubricants. Thus, for instance.it has been foundthat in the case of lubricating oils for cylinders ofaero-engines the presence of polycarboxylic acids in these oils results.in an appreciably reduced attack of the piston and the 20 cylinder wallthrough rust-formation.

As higher molecular polycarbomiic acids there may be considered bothsubstituted, e. g. containing groups of hydroxyls or esters, andnonsubstituted saturated or unsaturated acids. It is as essential,however, that more than one tree carboxyl group is present.

- Suitable poiycarboxylic acids are for instance those obtained by acondensation reaction of oleflnes with maleic acid, anhydride, whichreso action is related to them described by Diehls and Alder, Ann. 460,page 98 (i928) Ber. 62,

.pagelifi (1929) and Ann. 470, page 62, (1929).

and of which the following is a typical example:

200 grams of a highly cracked hydrocarbon 35 distillate boiling from 150to 200 0. obtained by cracking paraflln wax in the vapor phase andhaying a bromine number or 116 is heated with 140 grams maleic acidanhydride during 14 hours at 150460 0. and then for '30 hours at zoo-23040 6., whereafter it is fractionated under a vacuum of 13 'mm. mercury..146 grams of a fraction 'boiling from 155 to "165 C. are subsequentlyhydrated by boiling-for 2 hours with 500 milliliters of water to producethe free acid. Upon extrac 4,5 tion with ether an extract amounting to155 grams oflish'tyellow acid-reacting viscous oil is obtained. w

When adding .25 to this acidtoaminferallubricatingoibtheresultingblendedoilis capable of eifectivelypreventing corrosion of internal combustion engines, whether suchengines have been in use or not.

Another suitable acid is agaric or l-cetyl citric acid (Chem. Abst. 25,page 1213, 1931). 5

Further examples are polycarboxylic acids obtained by polymerization, e.g., by heating and/or boiling, voltolizing, etc), of fatty acids, oracids produced from polymerized fats by hydrolyzing, or saponifying sameand liberating the acids m from the soap.

The added quantities of polycarboxylic acids are, as a rule,comparatively small, e. g. less than 5%, in many cases even below 1%.

Example I The addition of 0.5% voltolized oleic acid to a minerallubricating oil, either compounded or not, is suflicient to obtain theabove efiect when using the oil as lubricant for cylinders ofaeroengines.

Example I! A technical quick-drying oil, upon the soapsolution obtainedbeing saponifled and acidified, yieldsa polycarboxylic acid-containingproduct 5 which when added in a quantity of 1% to a mineral lubricatingoil has the property of preventing rust-formation in acre-enginecylinders.

I claim: a

l. A lubricant capable of reducing corrosion in internal combustionengines, consisting essentially of a mineral lubricating 011 containingas an active anticorrosion ingredient a small quan-' tity of apolycarboxylic acid obtained by condensatio'n of maleic acid anhydrideand oleflnes.

V 2. A lubricant capable of reducing corrosion in internal combustionengines consisting essentially of a mineral lubricating oil containingas an active anti-corrosion ingredient less than 5% of a polycarboxylicacid obtained by condensation of maleic acid anhydride and an oleflne.

3. A lubricant capable of reducing corrosion in internal combustionengines consisting essentially of a mineral lubricating oil containingas an active anti corrosion ingredient less than 1% -of a polycarboxylicacid obtained by condensation ofmaleic acid anhydrlde and an oleflne.

FRANZ RUDOLF MOBER.

